A power supply device includes a coil, a first switch circuit that accumulates energy in the coil, and a plurality of second switch circuits that couple the coil to a plurality of output terminals. A first control unit generates a first control signal that controls the first switch circuit to turn on and off based on a combined value of a plurality of output voltages respectively output from the plurality of output terminals and a first reference value. A second control unit generates a second control signal that controls the plurality of second switch circuits to turn on and off in a cycle that is the same as the first control signal based on a first output voltage of the plurality of output voltages and a second reference value.